IRA tax treatment

Dear HMRC. I am a UK citizen and returned to the UK after 25 years of working in the US. I am resident in the UK for tax purposes and file self assessment returns annually. I have a traditional IRA from my time in the US and am not yet taking distributions from the IRA. I will need to start taking the minimum required distributions from the IRA in the near future and need to understand where to declare this income in the Foreign Pages section of my self assessment return. I am somewhat confused by the prior advice posted here as to whether or not the income is Foreign Pension or Foreign Interest. Thank you.

Hi Leonie,
Please have a look at:
DT19853 - Double Taxation Relief Manual: Guidance by country: United States of America: Notes for some guidance on IRA's.  
Payments made by the individual into an IRA, are made after tax relief is given to the individual by the employer.  
Payments from this pension are taxable in the USA.  
HMRC do not recognise IRA schemes as pensions, so for UK residents, they are taxed as income under interest and declared as foreign interest on a tax return (SA106).    
There is no US taxation if the pension is subject and liable to UK tax. If US tax is withheld, then the individual,  should seek a refund of this tax (file a form 1040NR).
HMRC will not give a credit for this tax against any UK tax charged on this income.
Thank you.

Many thanks, that is most helpful.